A. S. Shawali, Sobhi M. Gomha
Oct 14, 2002
Citations
0
Influential Citations
30
Citations
Journal
Tetrahedron
Abstract
Abstract 6-Benzyl-3-(arylmethylidenehydrazino)-as-triazin-5(4H)-ones 4 underwent regioselective cyclization upon treatment with either bromine in acetic acid containing sodium acetate or with ferric chloride in refluxing ethanol to give the respective s-triazolo[4,3-b]-as-triazin-7(8H)-ones 7 in overall good yields. The regioselectivity in the studied reactions was elucidated by comparison of 13C NMR spectra of 7 and their methyl derivatives with those of their regioisomers prepared by independent methods.